Container for photoresist liquid

Abstract

A blow molded container for high purity liquid chemicals having (1) an inner layer formed of a high purity resin comprising at least one member including olefinic polymers of ethylene, propylene, butene-1, 4-methyl-pentene-1, hexene-1 or octene-1 and copolymers of ethylene and olefins other than ethylene; (2) an intermediate layer of a solvent-barrier resin including polyamides, polyvinyl alcohols, poly(ethylene-co-vinyl alcohols), polyesters and polyphenylene oxides; and (3) an external layer formed of a light-shielding substance-containing resin composition. The lowest absorbance of the total layers of the container is greater than 2.0 measured at a wavelength of not more than 400 nm. The total layers also have an absorbance that does not exceed 1.62 measured at a wavelength of 600 nm. The container is especially good for holding photoresist liquids.

What is claimed is:  
     
       1. A blow molded container for photoresist liquid, the container having light-shielding properties in the ultraviolet light region while permitting some transmission of light rays in the visible light region, comprising an inner layer, an intermediate layer, and an external layer, wherein 
       (1) the inner layer is a resin comprising at least one olefinic polymer selected from polymers of ethylene, propylene, butene-1, 4-methyl-pentene-1, hexene-1 or octene-1 and copolymers of ethylene and olefins other than ethylene;  
       (2) the intermediate layer is a solvent-barrier resin comprising at least one member selected from the group consisting of polyamides, polyvinyl alcohol, copolymers of ethylene and vinyl alcohol, polyesters and polyphenylene oxides;  
       (3) the external layer is a resin composition containing a light-shielding substance;  
       (4) the lowest absorbance of the container is more than 2.0 determined at a wavelength of not more than 400 nm by spectrophotometer; and  
       (5) the absorbance of the container is not more than 1.62 determined at a wavelength of 600 nm by spectrophotometer.  
     
     
       2. The container of  claim 1 , further comprising an adhesive layer between the inner layer and the intermediate layer. 
     
     
       3. The container of  claim 1 , further comprising an adhesive layer between the intermediate layer and the external layer. 
     
     
       4. The container of  claim 1 , wherein the resin composition of the external layer comprises less than 5% by weight of a pigment dispersant consisting of at least one olefinic polymer selected from the group consisting of polyethylene and polypropylene having a number-average molecular weight of not less than 2×10 3 ; and 0.01 to 5% by weight of at least one light-shielding pigment selected from the group consisting of inorganic and organic pigments. 
     
     
       5. The container of  claim 1 , wherein the resin composition of the external layer comprises less than 2.5% by weight of an ultraviolet light absorber.